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Diffstat (limited to 'drivers/md/dm-emc.c')
-rw-r--r--drivers/md/dm-emc.c345
1 files changed, 0 insertions, 345 deletions
diff --git a/drivers/md/dm-emc.c b/drivers/md/dm-emc.c
deleted file mode 100644
index 3ea5ad4b7805..000000000000
--- a/drivers/md/dm-emc.c
+++ /dev/null
@@ -1,345 +0,0 @@
-/*
- * Copyright (C) 2004 SUSE LINUX Products GmbH. All rights reserved.
- * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
- *
- * This file is released under the GPL.
- *
- * Multipath support for EMC CLARiiON AX/CX-series hardware.
- */
-
-#include "dm.h"
-#include "dm-hw-handler.h"
-#include <scsi/scsi.h>
-#include <scsi/scsi_cmnd.h>
-
-#define DM_MSG_PREFIX "multipath emc"
-
-struct emc_handler {
- spinlock_t lock;
-
- /* Whether we should send the short trespass command (FC-series)
- * or the long version (default for AX/CX CLARiiON arrays). */
- unsigned short_trespass;
- /* Whether or not to honor SCSI reservations when initiating a
- * switch-over. Default: Don't. */
- unsigned hr;
-
- unsigned char sense[SCSI_SENSE_BUFFERSIZE];
-};
-
-#define TRESPASS_PAGE 0x22
-#define EMC_FAILOVER_TIMEOUT (60 * HZ)
-
-/* Code borrowed from dm-lsi-rdac by Mike Christie */
-
-static inline void free_bio(struct bio *bio)
-{
- __free_page(bio->bi_io_vec[0].bv_page);
- bio_put(bio);
-}
-
-static void emc_endio(struct bio *bio, int error)
-{
- struct dm_path *path = bio->bi_private;
-
- /* We also need to look at the sense keys here whether or not to
- * switch to the next PG etc.
- *
- * For now simple logic: either it works or it doesn't.
- */
- if (error)
- dm_pg_init_complete(path, MP_FAIL_PATH);
- else
- dm_pg_init_complete(path, 0);
-
- /* request is freed in block layer */
- free_bio(bio);
-}
-
-static struct bio *get_failover_bio(struct dm_path *path, unsigned data_size)
-{
- struct bio *bio;
- struct page *page;
-
- bio = bio_alloc(GFP_ATOMIC, 1);
- if (!bio) {
- DMERR("get_failover_bio: bio_alloc() failed.");
- return NULL;
- }
-
- bio->bi_rw |= (1 << BIO_RW);
- bio->bi_bdev = path->dev->bdev;
- bio->bi_sector = 0;
- bio->bi_private = path;
- bio->bi_end_io = emc_endio;
-
- page = alloc_page(GFP_ATOMIC);
- if (!page) {
- DMERR("get_failover_bio: alloc_page() failed.");
- bio_put(bio);
- return NULL;
- }
-
- if (bio_add_page(bio, page, data_size, 0) != data_size) {
- DMERR("get_failover_bio: bio_add_page() failed.");
- __free_page(page);
- bio_put(bio);
- return NULL;
- }
-
- return bio;
-}
-
-static struct request *get_failover_req(struct emc_handler *h,
- struct bio *bio, struct dm_path *path)
-{
- struct request *rq;
- struct block_device *bdev = bio->bi_bdev;
- struct request_queue *q = bdev_get_queue(bdev);
-
- /* FIXME: Figure out why it fails with GFP_ATOMIC. */
- rq = blk_get_request(q, WRITE, __GFP_WAIT);
- if (!rq) {
- DMERR("get_failover_req: blk_get_request failed");
- return NULL;
- }
-
- blk_rq_append_bio(q, rq, bio);
-
- rq->sense = h->sense;
- memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
- rq->sense_len = 0;
-
- rq->timeout = EMC_FAILOVER_TIMEOUT;
- rq->cmd_type = REQ_TYPE_BLOCK_PC;
- rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
-
- return rq;
-}
-
-static struct request *emc_trespass_get(struct emc_handler *h,
- struct dm_path *path)
-{
- struct bio *bio;
- struct request *rq;
- unsigned char *page22;
- unsigned char long_trespass_pg[] = {
- 0, 0, 0, 0,
- TRESPASS_PAGE, /* Page code */
- 0x09, /* Page length - 2 */
- h->hr ? 0x01 : 0x81, /* Trespass code + Honor reservation bit */
- 0xff, 0xff, /* Trespass target */
- 0, 0, 0, 0, 0, 0 /* Reserved bytes / unknown */
- };
- unsigned char short_trespass_pg[] = {
- 0, 0, 0, 0,
- TRESPASS_PAGE, /* Page code */
- 0x02, /* Page length - 2 */
- h->hr ? 0x01 : 0x81, /* Trespass code + Honor reservation bit */
- 0xff, /* Trespass target */
- };
- unsigned data_size = h->short_trespass ? sizeof(short_trespass_pg) :
- sizeof(long_trespass_pg);
-
- /* get bio backing */
- if (data_size > PAGE_SIZE)
- /* this should never happen */
- return NULL;
-
- bio = get_failover_bio(path, data_size);
- if (!bio) {
- DMERR("emc_trespass_get: no bio");
- return NULL;
- }
-
- page22 = (unsigned char *)bio_data(bio);
- memset(page22, 0, data_size);
-
- memcpy(page22, h->short_trespass ?
- short_trespass_pg : long_trespass_pg, data_size);
-
- /* get request for block layer packet command */
- rq = get_failover_req(h, bio, path);
- if (!rq) {
- DMERR("emc_trespass_get: no rq");
- free_bio(bio);
- return NULL;
- }
-
- /* Prepare the command. */
- rq->cmd[0] = MODE_SELECT;
- rq->cmd[1] = 0x10;
- rq->cmd[4] = data_size;
- rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
-
- return rq;
-}
-
-static void emc_pg_init(struct hw_handler *hwh, unsigned bypassed,
- struct dm_path *path)
-{
- struct request *rq;
- struct request_queue *q = bdev_get_queue(path->dev->bdev);
-
- /*
- * We can either blindly init the pg (then look at the sense),
- * or we can send some commands to get the state here (then
- * possibly send the fo cmnd), or we can also have the
- * initial state passed into us and then get an update here.
- */
- if (!q) {
- DMINFO("emc_pg_init: no queue");
- goto fail_path;
- }
-
- /* FIXME: The request should be pre-allocated. */
- rq = emc_trespass_get(hwh->context, path);
- if (!rq) {
- DMERR("emc_pg_init: no rq");
- goto fail_path;
- }
-
- DMINFO("emc_pg_init: sending switch-over command");
- elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 1);
- return;
-
-fail_path:
- dm_pg_init_complete(path, MP_FAIL_PATH);
-}
-
-static struct emc_handler *alloc_emc_handler(void)
-{
- struct emc_handler *h = kzalloc(sizeof(*h), GFP_KERNEL);
-
- if (h)
- spin_lock_init(&h->lock);
-
- return h;
-}
-
-static int emc_create(struct hw_handler *hwh, unsigned argc, char **argv)
-{
- struct emc_handler *h;
- unsigned hr, short_trespass;
-
- if (argc == 0) {
- /* No arguments: use defaults */
- hr = 0;
- short_trespass = 0;
- } else if (argc != 2) {
- DMWARN("incorrect number of arguments");
- return -EINVAL;
- } else {
- if ((sscanf(argv[0], "%u", &short_trespass) != 1)
- || (short_trespass > 1)) {
- DMWARN("invalid trespass mode selected");
- return -EINVAL;
- }
-
- if ((sscanf(argv[1], "%u", &hr) != 1)
- || (hr > 1)) {
- DMWARN("invalid honor reservation flag selected");
- return -EINVAL;
- }
- }
-
- h = alloc_emc_handler();
- if (!h)
- return -ENOMEM;
-
- hwh->context = h;
-
- if ((h->short_trespass = short_trespass))
- DMWARN("short trespass command will be send");
- else
- DMWARN("long trespass command will be send");
-
- if ((h->hr = hr))
- DMWARN("honor reservation bit will be set");
- else
- DMWARN("honor reservation bit will not be set (default)");
-
- return 0;
-}
-
-static void emc_destroy(struct hw_handler *hwh)
-{
- struct emc_handler *h = (struct emc_handler *) hwh->context;
-
- kfree(h);
- hwh->context = NULL;
-}
-
-static unsigned emc_error(struct hw_handler *hwh, struct bio *bio)
-{
- /* FIXME: Patch from axboe still missing */
-#if 0
- int sense;
-
- if (bio->bi_error & BIO_SENSE) {
- sense = bio->bi_error & 0xffffff; /* sense key / asc / ascq */
-
- if (sense == 0x020403) {
- /* LUN Not Ready - Manual Intervention Required
- * indicates this is a passive path.
- *
- * FIXME: However, if this is seen and EVPD C0
- * indicates that this is due to a NDU in
- * progress, we should set FAIL_PATH too.
- * This indicates we might have to do a SCSI
- * inquiry in the end_io path. Ugh. */
- return MP_BYPASS_PG | MP_RETRY_IO;
- } else if (sense == 0x052501) {
- /* An array based copy is in progress. Do not
- * fail the path, do not bypass to another PG,
- * do not retry. Fail the IO immediately.
- * (Actually this is the same conclusion as in
- * the default handler, but lets make sure.) */
- return 0;
- } else if (sense == 0x062900) {
- /* Unit Attention Code. This is the first IO
- * to the new path, so just retry. */
- return MP_RETRY_IO;
- }
- }
-#endif
-
- /* Try default handler */
- return dm_scsi_err_handler(hwh, bio);
-}
-
-static struct hw_handler_type emc_hwh = {
- .name = "emc",
- .module = THIS_MODULE,
- .create = emc_create,
- .destroy = emc_destroy,
- .pg_init = emc_pg_init,
- .error = emc_error,
-};
-
-static int __init dm_emc_init(void)
-{
- int r = dm_register_hw_handler(&emc_hwh);
-
- if (r < 0)
- DMERR("register failed %d", r);
-
- DMINFO("version 0.0.3 loaded");
-
- return r;
-}
-
-static void __exit dm_emc_exit(void)
-{
- int r = dm_unregister_hw_handler(&emc_hwh);
-
- if (r < 0)
- DMERR("unregister failed %d", r);
-}
-
-module_init(dm_emc_init);
-module_exit(dm_emc_exit);
-
-MODULE_DESCRIPTION(DM_NAME " EMC CX/AX/FC-family multipath");
-MODULE_AUTHOR("Lars Marowsky-Bree <lmb@suse.de>");
-MODULE_LICENSE("GPL");